The present invention relates to a formed strip such as a roll formed strip, and a roll forming method or system.
In particular, the present invention relates to a stage for forming tubes in a production system for producing heat exchangers for air conditioners, including stages for producing header pipes by press working to form a flat sheet or plate to a cylindrical shape, for producing U-shaped holders by roll forming from a metal strip, for inserting, in each holder, an inner fin formed by press forming or roll forming, for forming tubes, such as heat exchanger tubes, from each holder, for forming corrugated outer fins by a corrugate cutter, and for assembling heat exchanger tubes, outer fins, and header pipes.
Tubes for conveying a fluid such as refrigerant is widely used in heat exchange devices such as a condenser of a refrigeration cycle for a motor vehicle, an evaporator and a radiator. In one production method, a refrigerant tube is formed by bending a flat metal strip.